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17 lines
542 B
Racket
17 lines
542 B
Racket
10 years ago
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#lang racket/base
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(require racket/class "helper.rkt")
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(provide (all-defined-out))
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(define Variable
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(class* object% (printable<%>)
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(super-new)
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(define (repr) (format "<Variable ~a>" _name))
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(define/public (custom-print out quoting-depth) (print (repr) out))
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(define/public (custom-display out) (displayln (repr) out))
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(define/public (custom-write out) (write (repr) out))
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(init-field name)
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(field [_name name])))
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(define Variable? (is-a?/c Variable))
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(define Unassigned (new Variable [name "Unassigned"]))
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